Mustang Grapes (Vitis mustangensis) are native to the southern United States and grow wild throughout Texas. If you pluck one off the vine and have a taste, you’ll be in for a shock. These grapes have very high acidity and a harsh bitterness. They taste terrible, and the acidity is so high it can even irritate your skin or mouth. However, that hasn’t stopped people from using mustang grapes to make jams, juices, and wines for centuries.
So, how do you go about using these tiny little acid bombs to make palatable wine? The key is to harvest the grapes at the correct time and to treat the must with enough water, sugar, and additives. In north Texas, where we are, the month of July is usually the best time to pick the grapes, when they are plump and a deep purple color. Note though that the spring weather can wreak havoc on the growth of these grapes and some years the crops can be killed off entirely. Be sure to wear rubber gloves during the harvest to protect your hands from the acidity of the grapes. It is a great idea to have an Acid Test Kit at hand to test the acidity of the must. Most mustang grapes have such a high acidity that you will have to go beyond the scale in the instructions to find the true acidity of the must. Acidity can be adjusted with many methods, but potassium bicarbonate
is the most common additive to help balance the acid. Mustang Grapes have very little natural sugar content, and must have sugar added to raise the gravity high enough to make a decent wine.
After you have harvested your grapes, you need to crush them. This can be as easy as a bucket and a 2x4 block of wood or as specialized as a true wine press. Don’t be tempted to crush them with your feet unless you wear very clean rubber boots to protect your feet. I’ve seen a clever winemaker drill holes in the bottom of a bucket, place the grapes in the bucket, and then push down with another bucket to crush the juice out of the holes into another container to collect the juice while leaving the skins behind. Leaving the skins out will make a white wine, but removes much of the natural flavor found in the skins of the mustang grapes. On the other hand, wines fermented with the skins must be carefully watched and taste tested to ensure the wine does not take on too much of the astringent tannins found in the grape skin.
The following is a basic recipe for making 1 gallon of a semi sweet red mustang grape wine.
-8-10 lbs.black Mustang Grapes
-1 nylon mesh bag for straining
-2 lbs. corn sugar
-5 pints water
-1 tsp. Pectic enzyme
-1 campden tablet [crushed]
-Potassium Bicarbonate to raise pH, aka reduce acidity
-71B-122 or Montrachet wine yeast
-Wine Nutrient and Yeast Energizer
-Potassium Sorbate or Wine Conditioner
1. Wash your grapes to remove any dirt and remove the stems, then place them in a nylon or muslin bag.
2. Boil the water or use a source of clean sanitized water. Hot water helps the sugar dissolve.
3. Crush your grapes in whichever method you like best, and add them to the fermenter, still in the bag.
4. Add the sugar to your fermenter.
5. Add the water to your fermenter.
6. Stir well to dissolve the sugar.
7. Put the lid on your fermenter and allow to cool to room temperature if you used hot water.
8. Using your hydrometer, check the gravity of the must.
9. Add crushed Campden tablet and let sit covered for 5-10 hours.
10. Add pectic enzyme and let sit again for another 10 hours.
11. Add yeast, nutrient, and energizer to mixture and stir. Using a sanitized spoon, push the grapes under the surface.
12. Stir 2-3 times daily for a week. Make sure the gravity is around 1.020 or lower.
13. Measure acidity using the acid test kit and modify pH as needed with the potassium bicarbonate.
14. Transfer the wine to a secondary fermenter, and remove the bag with the grapes, letting as much of the wine strain out of the bag as possible. Discard the bag of grapes.
15. Add Potassium Sorbate and sugar, or use Wine Conditioner to stop fermentation and back sweeten.
16. Bottle the wine and let sit for at least 1 month before tasting.
Make sure to check out our Come and Brew It Radio episode about making wine from kits and making wine from grapes and other fruits.
Austin has been brewing beer commercially and at home for the past decade. Feel free to contact him with any questions or comments at firstname.lastname@example.org